1. Field of the Invention
The present invention relates to a control apparatus and, more particularly, to such a control apparatus which is operable to control the path of movement of a work object and which displays the path to be followed by the work object for convenient reference.
2. Description of the Prior Art
It is frequently necessary in the operation of such work objects as security cameras, movable lights, sensing devices, sprinklers and the like to control the path of movement of the work object during operation. For example, in all of the foregoing instances, the work objects are moved during operation along a path which, for reasons individual thereto, must be controlled. In these exemplary cases, the work objects are individually moved in reciprocal motion along arcuate paths which may be all, or any divisible sector, of a three hundred and sixty degree (360.degree.) path of travel about an axis of rotation. A variety of devices are conventionally employed for controlling the range of movement of the work object within such a path of movement.
For example, in the case of sprinklers, it is known to employ control mechanisms which allow the adjustment of the sector of movement of a reciprocating sprinkler. Illustrative of one such control mechanism is that disclosed in the Bruninga U.S. Pat. No. 4,892,252. The patent discloses a pattern control assembly which cooperates with a lever and a resilient post reversing mechanism in the control of the path of fluid released from the sprinkler. Thus, the sprinkler is adjustable to control the sector of a three hundred and sixty degree (360.degree.) circle within which the sprinkler reciprocates to release irrigation water. Adjustment members are employed to define the sector of the circle within which the sprinkler reciprocates and the adjustment members are positionable relative to each other to define the sector so selected.
Prior art control devices for sprinklers and other such work objects, while operable within limited abilities to perform certain operational objectives, are otherwise ill suited to the performance of their stated tasks. The devices are notoriously complex, temperamental, expensive, difficult to operate and chronically subject to malfunction as a result of tampering or inadvertent misadjustment. Because of the expense involved, such devices for sprinklers typically are employed in commercial applications such as golf courses, parks, business and industrial complexes, and other public facilities where the devices are employed in large numbers. They are, as a consequence, exposed to damage or tampering by passersby. In such installations, the need for adjustment thereof requires that access be provided to the adjustment mechanism. However, such access renders the devices chronically subject to tampering by passersby who may intentionally misadjust the mechanism. In other instances, the devices are exposed to impact by lawn mowers, foot traffic and the like which may cause inadvertent misadjustment of the control mechanisms. In still other instances, the requirement that such devices at the time of installation and thereafter be adjusted by untrained or only partially trained personnel further increases the likelihood that they are misadjusted during their useful lives. Still further, the complexity of such prior art devices renders them sensitive to malfunction as a result of damage due to impact.
There are still other inherent disabilities in prior art devices designed for the same purpose which render them less than satisfactory in the performance of their operational objectives. In those few prior art devices which have any means for readily indicating the sector to which such adjustment has been made, the indicating mechanism itself is, to varying degrees, inaccurate, misleading and, at best, only remotely indicative of the actual sector to which the mechanism has been adjusted. Furthermore, such prior art indicating mechanisms are typically obscure and require a certain minimum level of understanding before the information intended to be imparted thereby is understood. Since, as previously noted, the adjustment of such devices is characteristically performed by persons having little or no training, the frequency with which unintended misadjustment occurs is significantly higher than would otherwise be deemed to be acceptable.
As also previously noted, the very complexity of such prior art devices ensures that the cost thereof is significantly beyond the range within which small businesses, homeowners and other entities of limited means could afford to employ such devices. There has not, heretofore, been such a prior art device which was available at a cost suited to such small operators.
Still further, such prior art devices are not suited to universal application in that they inherently must be employed only in the specific areas of application for which they were specifically designed. There has not heretofore been a device adapted for the same broad purpose which was capable of virtually universal application in the control of work objects of a wide variety of types and areas of application.
Therefore, it has long been known that it would be desirable to have a control apparatus adapted to control the path of movement of a work object which is capable of controlling the path of movement of the work object over a long operational life; which minimizes the risk of misadjustment as a result of tampering or inadvertent missetting thereof; which affords an immediately recognizable and precise display of the range of movement to which it has been set so as to avoid inadvertent misadjustment; which possesses a simplicity of structure and operation ensuring a long operational life and a minimum purchase price; and which otherwise is entirely effective in achieving its operational objectives.